【０００１】
【発明の属する技術分野】
本発明は、太陽光のように時事刻々と入射角度が変化する入射光を入射角度に関係なく略一定方向へと制限して放射させる光路抑制レンズとこれを用いた集光装置に関するものである。
【０００２】
【従来の技術】
１００年後には化石燃料は枯渇し、２００年後には原子力発電も無くなると言われており、人類にとって近い将来、残されたエネルギー源は太陽光によるエネルギーと核融合のみとなる厳しい現実を迎えなくてはいけない。また、化石燃料依存による二酸化炭素増加の結果、地球の温暖化が促進され人類絶滅の危機さえ懸念されている。これを回避する意味でもエネルギー源の多くを太陽光エネルギーへと早期に切り替えることが必要である。そのためには、太陽光エネルギーを効率良く利用する技術開発が不可欠である。そこで、これまでに太陽光エネルギーを凝縮させる為に凸レンズや凹面鏡を用いた研究がなされている。凸レンズや凹面鏡によれば太陽光を焦点に集光させることで濃縮が可能であった。しかし、凸レンズや凹面鏡によれば常時、入射光を一定方向から入射させる必要があるため時事刻々と変化する太陽光の入射角度に応じて、入射光の向きが常に一定になるように追尾させる必要があった。そのため、制御系も複雑になる等設備が大掛かりになってしまい希薄な太陽光エネルギーを利用する割りには設備費が高額なものとなり実用には不向きとされていた。また、曇天の日には、太陽光は散乱してしまうため集光不能であった。
【０００３】
そこで、鈴木は、これまでに「集光レンズと前記集光レンズを用いた集光方法」（特開２０００−５６１０２号公報）、光路抑制レンズ（特開２００２−２１４４０６号公報）、光路抑制レンズ（特開２００２−３５７７０２号公報）にて開示しているように、地表面の１平方メートルあたりに１ｋＷ程度と極めて希薄なエネルギーである太陽光を従来の集光技術では実現しえない程に効率よく濃縮する集光レンズを開発した。これらのレンズによれば、様々な方向から入射する光の透過後の進行方向を入射角度に関係なく略一定に保つことができた。例えば、時事刻々と入射角度が変化する太陽光を略鉛直下向きに保つことができる等、入射角度に関係なく透過後の光の進行方向を自在に設定できた。したがって、複数のレンズを使用して各レンズの透過光が一定の位置に集中する様に配置するだけで、時刻の変化で太陽光の入射角度が変化しようとも、曇りの日で入射光が散乱光であっても、太陽光を集光させることができた。また、全体を略平板状に構成でき、設備の省スペース、低コストの面でも有効であった。
【０００４】
【発明が解決しようとする課題】
しかし、上記レンズによれば、全ての入射角度に対して透過光の進行方向を完全に一定方向に保つことができるわけではなく、少しでも精度を高めることが望まれていた。また、透過光の進行方向を略一定方向に保てる入射角度の上限を少しでも大きくすることが望まれていた。
【０００５】
そこで、本発明は、透過光の進行方向を略一定方向に保てる精度と、透過光の進行方向を略一定方向に保てる入射角度範囲とを従来よりも高めた光路抑制レンズとこれを用いた集光装置の提供を課題とするものである。
【０００６】
【課題を解決するための手段】
請求項１の発明にかかる光路抑制レンズは、一端面方向から見た同一断面形状を保って奥行き方向に略線状に連なる複数の集光部が幅方向に略平行に並んで連結されてなる透明な略平板状体であり、前記各集光部が、一端面方向から見て入射面側略中央に位置する平面部と、前記平面部の左右の各端に続いて放射面側に略４５°で傾斜し前記平面部の４乃至５倍の幅を有する傾斜面部と、前記各傾斜面部の他端に続いて凹状曲面をなし隣接する他の集光部の傾斜面部へと繋がる連結面と、各集光部の放射面側略中央に位置し凹状曲面をなし臨界角度で入射する入射光を全反射により跳ね上げる跳ね上げ面と、前記跳ね上げ面に続き凸状曲面で前記傾斜面の５分の２乃至５分の３の幅を有する集光面と、前記集光面に続いて凹状の曲面をなし前記傾斜面の５分の１乃至３分の１の幅を有する分散面と、前記分散面に続き収束して突出する第一氷柱状部と、前記第一氷柱状部に続き隣接する他の集光部の第一氷柱状部へと繋がり収束して突出する第二氷柱状部とを備えるものである。なお、光路抑制レンズを構成する透明な素材には屈折率が１．４９のメタアクリル（ＭＭＡ）がある。
【０００７】
したがって、請求項１の発明の光路抑制レンズによれば、入射光の入射角度が６０°以上と比較的大きい場合には、１つの集光部の有する２つの傾斜面部のうちの一方から入射光の大部分が入射し、その対向する放射面から放射後に再び別の放射面から入射面へと逆進行し他方の傾斜面部で全反射され透過光の進行方向が略一定方向に制限される。また、集光面は一方の傾斜面部から入射した光を凸状形状していることにより収束させて他方の傾斜面部へと到達しやすくする。また、入射面のうち比較的上方である平面部及びその近傍より入射した光は、入射光の入射角度が６０°以上と比較的大きい場合に跳ね上げ面により全反射されて傾斜面部へと導かれ最終的に略鉛直下向きに補正される。また、傾斜面部の下方或は連結面より入射した入射光は、第一氷柱状部或は第二氷柱状部により、対向する面間で入射角度に応じて複数回全反射されて透過光の進行方向を略鉛直下向きに制限される。集光面や第一氷柱状部、第二氷柱状部へと至ることのできなかった透過光は、凹面状をしている分散面により放射状に拡散され直接鉛直下向きに放射される光と他の傾斜面部へ戻って全反射により鉛直下向きにされる光とに切り分けられる。
【０００８】
請求項２の発明にかかる光路抑制レンズは、請求項１の光路抑制レンズにおいて、入射面側から前記第二氷柱状部の内部へと肉厚を略一定に保って切り欠かれた切欠部を備えたものある。
【０００９】
したがって、請求項２の発明の光路抑制レンズによれば、請求項１の発明の光路抑制レンズに作用に加えて、集光部全領域の中でもそのままでは最も肉厚が大きくなる第二氷柱状部の肉厚が切欠部によって大きくなるのを阻止される。
【００１０】
請求項３の発明にかかる光路抑制レンズは、請求項１の光路抑制レンズにおいて、光路抑制レンズが奥行き方向の一端面方向から見て幅方向の一端に曲率一定で凸状の曲面からなる凸状連結曲面を有し、他端に前記凸状連結曲面と略同一曲率で前記凸状連結曲面に噛み合わせ自在な凹状の曲面からなる凹状連結曲面を有し、これら凸状連結曲面と凹状連結曲面の位置関係が２つの光路抑制レンズにおいて一方の光路抑制レンズの凸状連結曲面と他方の光路抑制レンズの凹状連結曲面とを噛み合わせたとき、２つの光路抑制レンズが略線対称な位置関係を保つ位置であり、２つの光路抑制レンズの略線対称な対称軸に中心を置くものである。
【００１１】
したがって、請求項３の発明の光路抑制レンズによれば、請求項１の発明の光路抑制レンズに作用に加えて、２つの光路抑制レンズの集光部が連結位置で角度を変えても略線対称な位置関係に保たれる。
【００１２】
請求項４の発明にかかる集光装置は、太陽光のエネルギーを受光して取り出す受光部を有し、南北方向に見て複数の請求項１の各光路抑制レンズを放射光が前記受光部に向かう角度になるように配置したものである。
【００１３】
ここで、受光部には太陽光のエネルギーを熱エネルギーとして蓄積する蓄熱槽あるいは、太陽電池や蒸気機関を用いて電気エネルギーに変換するもの、吸収冷凍サイクルの再成器等がある。
【００１４】
したがって、請求項４の発明の集光装置によれば、複数の請求項１の各光路抑制レンズのいずれに入射した入射光も時事刻々と変化する入射角度に略依存することなく透過後には全て受光部へと向って集光される。
【００１５】
【発明の実施の形態】
以下、本発明の実施の形態について説明をする。図１は本発明の実施の形態の光路抑制レンズを奥行き方向の一端面から見たところを示す端面図である。本発明の実施の形態の光路抑制レンズ１は、屈折率が略１．４９の透明なメタアクリル樹脂（以降の説明では単にＭＭＡと呼ぶ）からなり、図１に示すように、奥行き方向の一端面から見ると同一形状をした複数の集光部２が連結された形状をしている。各集光部２は奥行き方向に略線状に連なっており、光路抑制レンズ１は全体が略平板状をしている。本発明の実施の形態の光路抑制レンズ１は、以下に説明するように、地球の自転の影響により時事刻々と入射角度が変化する太陽光の進行方向を略一定の範囲に抑制できる。特に、その効果が日の出から日没に至る全日照時間帯において得られるため据え置きで使用することができる。しかも、全体が平板状で、省スペース化と製造コストの低減ができる。
【００１６】
図２に示すように、各集光部２は一端面方向から見て入射面側略中央に位置する平面部３と、前記平面部３の左右の各端に続いて放射面側に略４５°で傾斜し前記平面部３の４乃至５倍の幅を有する傾斜面部４と、前記各傾斜面部４の他端に続いて凹状曲面をなし隣接する他の集光部２の傾斜面部４へと繋がる連結面５とを備えている。図２は本発明の実施の形態の光路抑制レンズの集光部を示す拡大端面図である。また、集光部２は、放射面側に各集光部２の放射面側略中央に位置し凹状曲面をなし臨界角度で入射する入射光を全反射により跳ね上げる跳ね上げ面６と、前記跳ね上げ面６に続き凸状曲面で前記傾斜面の５分の２乃至５分の３の幅を有する集光面７と、前記集光面７に続いて凹状の曲面をなし前記傾斜面４の５分の１乃至３分の１の幅を有する分散面８と、前記分散面８に続き収束して突出する第一氷柱状部９と、前記第一氷柱状部９に続き隣接する他の集光部２の第一氷柱状部９へと繋がり収束して突出する第二氷柱状部１０とを備えている。第二氷柱状部１０は第一氷柱状部９に比べて大きめであるが、入射面側の連結面５に第二氷柱状部１０全体の肉厚が略一定になるように切欠部５ａが形成されている。切欠部５ａは集光部２全領域の中でもそのままでは最も肉厚が大きくなる第二氷柱状部１０の肉厚が大きくなるのを阻止し、金型による成形加工時の変形歪みを最小限に低減し設計通りの光路抑制効果を発揮できる。
【００１７】
前記光路抑制レンズ１の奥行き方向の一端面方向から見て幅方向の一端には、図３の（ａ）に示すように、曲率一定で凸状の曲面からなる凸状連結曲面１１が形成され、他端には、図３の（ｂ）に示すように、前記凸状連結曲面１１と略同一曲率で前記凸状連結曲面１１に噛み合わせ自在な凹状の曲面からなる凹状連結曲面１２が形成されている。図３の（ａ）は本発明の実施の形態の光路抑制レンズの凸状連結曲面１１を示す説明図、（ｂ）は本発明の実施の形態の光路抑制レンズの凹状連結曲面１２を示す説明図である。これら凸状連結曲面１１と凹状連結曲面１２の位置関係は、図４に示すように、２つの光路抑制レンズ１において一方の光路抑制レンズ１の凸状連結曲面１１と他方の光路抑制レンズ１の凹状連結曲面１２とを噛み合わせたとき、２つの光路抑制レンズ１が略線対称な位置関係を保つ位置であり、２つの光路抑制レンズ１の略線対称な対称軸１３に中心１４が位置している。図４は複数の本発明の実施の形態の光路抑制レンズの連結状態を示す説明図である。そのため、図５に示すように、２つの光路抑制レンズ１が連結位置で角度を変えても略線対称な位置関係に保たれ、複数の光路抑制レンズ１を容易に見栄え良く配列させることができる。図５は図４に続く複数の本発明の実施の形態の光路抑制レンズの連結状態を示す説明図である。
【００１８】
続いて、本発明の実施の形態の光路抑制レンズ１の特性について図６乃至図１０に従って説明する。なお、以下の説明においては、集光部２の線状に連続する方向を南北に向けて使用するものとする。図６は本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度１５°で光を入射させた様子を示す説明図である。図７は本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度３０°で光を入射させた様子を示す説明図である。図８は本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度４５°で光を入射させた様子を示す説明図である。図９は本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度６０°で光を入射させた様子を示す説明図である。図１０は本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度７５°で光を入射させた様子を示す説明図である。図６乃至図１０に示すように、本実施の形態の光路抑制レンズ１によれば、入射角度を様々に変えても透過光の進行方向は略鉛直下向きとなり略一定方向に保たれる。この特性は、全ての入射角度において図示したわけではないが、入射角度が０°から９０°に至る全範囲において発揮される。
【００１９】
では、透過光の進行方向を入射角度に関係なく略一定に保てる原理について詳述する。傾斜面部４は図９や図１０に示すように入射角度が６０°以上と比較的大きい場合に、集光部２の２つの傾斜面部４の一方から入射した光がその対向する放射面から放射後に再び他の放射面から入射面へと逆進行する場合に全反射させることにより再び光の進行方向を放射面側へと戻してやるものである。これにより透過光の進行方向が図面に向かって鉛直した向きに保たれる。また、このように入射角度が比較的大きい場合には１つの集光部２の有する２つの傾斜面部４のうちの一方から入射光の大部分が入射し他方の傾斜面部４で全反射されるが、集光面７は一方の傾斜面部４から入射した光を凸状形状していることにより収束させて他方の傾斜面部４へと到達しやすくするものである。
【００２０】
なお、入射面のうち比較的上方（特に平面部３）より入射した光は、何もしなければ進行方向を鉛直下向きに変えないまま透過しようとするので、入射角度が比較的大きい場合には問題であるが、図９および図１０に示すように、跳ね上げ面６により全反射させることで傾斜面部４へと入射光が導かれ最終的に略鉛直下向きに補正される。
【００２１】
図７乃至図９に示すように、傾斜面部４の下方或は連結面５より入射した入射光は、第一氷柱状部９或は第二氷柱状部１０により、対向する面間で入射角度に応じて複数回全反射させて透過光の進行方向を略鉛直下向きに制限する。分散面８は、図９に示すように、集光面７や第一氷柱状部９、第二氷柱状部１０へと至ることのできなかった透過光を凹面状をしていることで放射状に拡散することによって、直接鉛直下向きに放射させる光と他の傾斜面部４へ戻して全反射により鉛直下向きにする光とに切り分けている。以上のような原理により本実施の形態の光路抑制レンズ１は、様々な入射角度で入射する入射光の進行方向を略一定の方向に保って放射させることができる。
【００２２】
なお、光路抑制レンズ１の１つの集光部２は一端面方向から見て左右対称形であり、入射角度が上記説明で示した場合と反対方向へと９０°に至る全範囲においても同様に透過光の進行方向を略一定方向へと抑制する。したがって、入射角度が０°から±９０°に至る全範囲において透過光の進行方向を略一定の方向に保つことができる。
【００２３】
以上のような特性を有する本発明の実施の形態の光路抑制レンズ１は、図１１に示すように、ドーム状に複数配置するだけで地球の自転の影響により時事刻々と変化する太陽光を所定範囲に集光させることができる。図１１は本発明の実施の形態の光路抑制レンズを用いた集光装置の一例を示す説明図である。図１１に示す集光装置２１は、南北方向に見て複数の光路抑制レンズ１を図３乃至図５で説明した凸状連結曲面１１と凹状連結曲面１２とで回動自在に連結して、各光路抑制レンズ１からの放射光が１点に集中する角度になるように配置したものであり、放射光が集中する位置には太陽光のエネルギーを受光して取り出す受光部２２が配置されている。ここで、受光部２２には太陽光のエネルギーを熱エネルギーとして蓄積する蓄熱槽あるいは、太陽電池や蒸気機関を用いて電気エネルギーに変換するもの、吸収冷凍サイクルの再成器等がある。
【００２４】
そして、上方からの入射光は、図１１に２点鎖線で示すように、入射前は時事刻々と入射角度が変化しているが、光路抑制レンズ１へと入射する入射角度に略依存することなく受光部２２に向って集光される。
【００２５】
このように、本発明の実施の形態の光路抑制レンズ１を用いた集光装置２１によれば、受光部２２には太陽光エネルギーが凝縮され、直射日光よりも高濃度の太陽光エネルギーを得ることができる。特に、冬期や曇天の日のように太陽光が通常より希薄或いは散乱している場合であっても太陽光を集光できる。しかも、本発明の実施の形態の光路抑制レンズ１は、入射角度が０°から±９０°に至る全範囲において透過光の進行方向を略一定の方向に保つことができるので、設置した光路抑制レンズ１を入射光の入射角度に合わせて追尾させる等の複雑な処理を１日を通して一切する必要がない。そのため、極めて安価に、太陽光エネルギーの凝縮が行え、有効に利用することができる。例えば、受光部２２が蓄熱槽の場合には、温湯を得る他、暖房の熱源、吸収冷凍サイクルの熱源、太陽熱発電等様々な用途が考えられる。また、受光部２２が太陽電池パネルである場合には太陽光発電を直接行うことができる。特に、吸収式冷凍サイクルを稼動させる場合や太陽光発電を行う場合には、エネルギーの有効利用ができるだけでなく、電力需要のピークカットを促進でき、電力会社の発電設備を縮小できる。
【００２６】
ところで、本発明の実施の形態の光路抑制レンズ１は、屈折率が１．４９の透明なメタアクリル樹脂（ＭＭＡ）からなっており、この屈折率の場合に最適に透過光の進行方向を略一定角度範囲に保てる形状に設計されているが、屈折率に見合って最適に透過光の進行方向を略一定角度範囲に保てる形状に設計されていれば屈折率の異なる他の素材からなっていても構わない。
【００２７】
【発明の効果】
本発明は、以上説明したように構成されているので、以下に記載されるような効果を奏する。
【００２８】
請求項１の発明の光路抑制レンズによれば、入射光の入射角度が６０°以上と比較的大きい場合には、１つの集光部の有する２つの傾斜面部のうちの一方から入射する入射光の大部分が他方の傾斜面部で全反射され透過光の進行方向が略一定方向に制限され、凸状形状をした集光面が傾斜面部から入射した光を収束させて他方の傾斜面部へと到達しやすくし、また、入射面のうち比較的上方である平面部及びその近傍より６０°以上と比較的大きい入射角度で入射した入射光が跳ね上げ面により全反射されて傾斜面部へと導かれ最終的に略鉛直下向きに補正され、さらに、傾斜面部の下方或は連結面より入射した入射光が、第一氷柱状部或は第二氷柱状部により、対向する面間で入射角度に応じて複数回全反射されて透過光の進行方向を略鉛直下向きに制限され、さらに、集光面や第一氷柱状部、第二氷柱状部へと至ることのできなかった透過光が、凹面状をしている分散面により放射状に拡散され直接鉛直下向きに放射される光と他の傾斜面部へ戻って全反射により鉛直下向きにされる光とに切り分けられるので、時事刻々と入射角度が変化する入射光の進行方向を日の出から日没までの終日を通して、極めて効率良く略一定方向に抑制することができる。
【００２９】
請求項２の発明の光路抑制レンズによれば、請求項１の発明の光路抑制レンズに効果に加えて、集光部全領域の中でもそのままでは最も肉厚が大きくなる第二氷柱状部の肉厚が切欠部によって大きくなるのを阻止されるので、金型による成形加工時の変形歪みを最小限に低減され設計通りの光路抑制効果を発揮できる。
【００３０】
請求項３の発明の光路抑制レンズによれば、請求項１の発明の光路抑制レンズに効果に加えて、２つの光路抑制レンズが連結位置で角度を変えても略線対称な位置関係に保たれるので、複数の光路抑制レンズを容易に見栄え良く配列させることができる。
【００３１】
請求項４の発明の集光装置によれば、複数の請求項１の各光路抑制レンズのいずれに入射した入射光も時事刻々と変化する入射角度に略依存することなく透過後には全て受光部へと向って集光されるので、受光部には太陽光エネルギーが凝縮され、直射日光よりも高濃度の太陽光エネルギーを得ることができる。特に、冬期や曇天の日のように太陽光が通常より希薄或いは散乱している場合であっても太陽光を集光できる。しかも、入射角度が０°から±９０°に至る全範囲において透過光の進行方向を略一定の方向に保つことができるので、設置した光路抑制レンズを入射光の入射角度に合わせて追尾させる等の複雑な処理を１日を通して一切する必要がない。そのため、極めて安価に、太陽光エネルギーの凝縮が行え、有効に利用することができる。例えば、受光部が蓄熱槽の場合には、温湯を得る他、暖房の熱源、吸収冷凍サイクルの熱源、太陽熱発電等様々な用途が考えられる。また、受光部が太陽電池パネルである場合には太陽光発電を直接行うことができる。特に、吸収式冷凍サイクルを稼動させる場合や太陽光発電を行う場合には、エネルギーの有効利用ができるだけでなく、電力需要のピークカットを促進でき、電力会社の発電設備を縮小できる。
【図面の簡単な説明】
【図１】本発明の実施の形態の光路抑制レンズを奥行き方向の一端面から見たところを示す端面図である。
【図２】本発明の実施の形態の光路抑制レンズの集光部を示す拡大端面図である。
【図３】（ａ）が本発明の実施の形態の光路抑制レンズの凸状連結曲面を示す説明図、（ｂ）が本発明の実施の形態の光路抑制レンズの凹状連結曲面を示す説明図である。
【図４】複数の本発明の実施の形態の光路抑制レンズの連結状態を示す説明図である。
【図５】図４に続く複数の本発明の実施の形態の光路抑制レンズの連結状態を示す説明図である。
【図６】本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度１５°で光を入射させた様子を示す説明図である。
【図７】本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度３０°で光を入射させた様子を示す説明図である。
【図８】本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度４５°で光を入射させた様子を示す説明図である。
【図９】本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度６０°で光を入射させた様子を示す説明図である。
【図１０】本発明の実施の形態の光路抑制レンズに奥行き方向の一端面方向から見て入射角度７５°で光を入射させた様子を示す説明図である。
【図１１】本発明の実施の形態の光路抑制レンズを用いた集光装置の一例を示す説明図である。
【符号の説明】
１ 光路抑制レンズ
２ 集光部
３ 平面部
４ 傾斜面部
５ 連結面
５ａ 切欠部
６ 跳ね上げ面
７ 集光面
８ 分散面
９ 第一氷柱状部
１０ 第二氷柱状部
１１ 凸状連結曲面
１２ 凹状連結曲面
１３ 対称軸
１４ 中心
２１ 集光装置
２２ 受光部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical path suppressing lens that radiates incident light whose incident angle changes with time, such as sunlight, in a substantially constant direction regardless of the incident angle, and a condensing device using the same. .
[0002]
[Prior art]
It is said that fossil fuels will be depleted in 100 years and nuclear power will disappear in 200 years. In the near future, the remaining energy source will not be faced with the harsh reality of being only solar energy and nuclear fusion. must not. In addition, as a result of the increase in carbon dioxide due to dependence on fossil fuels, global warming is promoted and there is concern about even the danger of human extinction. In order to avoid this, it is necessary to switch many energy sources to solar energy at an early stage. To that end, it is essential to develop technology that efficiently uses solar energy. Therefore, research using a convex lens and a concave mirror has been made so far to condense sunlight energy. Concentration was possible by concentrating sunlight at the focal point using a convex lens or concave mirror. However, according to the convex lens and concave mirror, it is necessary to always enter the incident light from a certain direction, so it is necessary to track the incident light so that the direction of the incident light is always constant according to the incident angle of sunlight that changes every moment. was there. Therefore, the control system becomes complicated and the equipment becomes large, and the equipment cost becomes high for using the dilute solar energy, which is not suitable for practical use. Also, on a cloudy day, sunlight could not be collected because it was scattered.
[0003]
Therefore, Suzuki has so far described “a condensing lens and a condensing method using the condensing lens” (Japanese Patent Laid-Open No. 2000-56102), an optical path suppressing lens (Japanese Patent Laid-Open No. 2002-214406), and an optical path suppressing lens. As disclosed in Japanese Patent Application Laid-Open No. 2002-357702, sunlight is an extremely dilute energy of about 1 kW per square meter of the ground surface, which is so efficient that it cannot be realized with conventional light collecting technology. We have developed a condensing lens that concentrates well. According to these lenses, the traveling direction after transmission of light incident from various directions can be kept substantially constant regardless of the incident angle. For example, the traveling direction of light after transmission can be freely set regardless of the incident angle, such as being able to keep sunlight whose incident angle changes from moment to moment almost vertically downward. Therefore, even if the incident angle of sunlight changes with time, the incident light is scattered on a cloudy day simply by using multiple lenses so that the transmitted light from each lens is concentrated at a certain position. Even with light, sunlight could be collected. Moreover, the whole can be comprised in substantially flat form, and it was effective also in terms of the space-saving of equipment, and low cost.
[0004]
[Problems to be solved by the invention]
However, according to the lens, it is not possible to keep the traveling direction of transmitted light in a completely constant direction with respect to all incident angles, and it has been desired to improve the accuracy as much as possible. Further, it has been desired to increase the upper limit of the incident angle that can keep the traveling direction of the transmitted light in a substantially constant direction.
[0005]
In view of this, the present invention provides an optical path suppression lens having an accuracy that can keep the traveling direction of transmitted light in a substantially constant direction and an incident angle range that can keep the traveling direction of transmitted light in a substantially constant direction, and a collection using the same. An object is to provide an optical device.
[0006]
[Means for Solving the Problems]
The optical path suppression lens according to the first aspect of the present invention is formed by connecting a plurality of condensing portions that are substantially linear in the depth direction while maintaining the same cross-sectional shape as viewed from one end surface direction, and are arranged in parallel in the width direction. It is a transparent substantially flat body, and each condensing part is substantially on the radiation surface side following the flat part located substantially in the center of the incident surface side when viewed from the one end face direction, and the left and right ends of the flat part. An inclined surface portion that is inclined at 45 ° and has a width 4 to 5 times that of the flat surface portion, and a connecting surface that forms a concave curved surface following the other end of each inclined surface portion and is connected to an inclined surface portion of another condensing portion adjacent thereto A bounce surface that is located approximately at the center on the radiation surface side of each condensing unit and that forms a concave curved surface and bounces incident light incident at a critical angle by total reflection, and a convex curved surface that follows the bounce surface and the inclined surface A condensing surface having a width of two-fifths to three-fifths and a concave curved surface following the condensing surface A dispersion surface having a width of one-fifth to one-third of the inclined surface; a first icicle-shaped portion that converges and protrudes following the dispersion surface; and another cluster adjacent to the first icicle-shaped portion. A second icicle-shaped portion that is connected to the first icicle-shaped portion of the light portion and converges and protrudes. A transparent material constituting the optical path suppressing lens is methacryl (MMA) having a refractive index of 1.49.
[0007]
Therefore, according to the optical path suppressing lens of the first aspect of the present invention, when the incident angle of the incident light is relatively large as 60 ° or more, the incident light is incident from one of the two inclined surface portions of the one light collecting portion. Most of the incident light is incident, and after radiating from the opposite radiation surface, the light travels backward from another radiation surface to the incident surface again, is totally reflected by the other inclined surface portion, and the traveling direction of transmitted light is limited to a substantially constant direction. In addition, the light converging surface has a convex shape so that the light incident from one inclined surface portion is converged to easily reach the other inclined surface portion. In addition, light incident from a plane portion that is relatively above the incident surface and the vicinity thereof are totally reflected by the jumping surface and guided to the inclined surface portion when the incident angle of the incident light is relatively large at 60 ° or more. Finally, it is corrected substantially vertically downward. Incident light incident below the inclined surface or from the connecting surface is totally reflected a plurality of times by the first icicle-shaped portion or the second icicle-shaped portion between the opposing surfaces according to the incident angle, and transmitted light is transmitted. The traveling direction is limited to a substantially vertical downward direction. The transmitted light that could not reach the condensing surface, the first icicle-shaped part, or the second icicle-shaped part is diffused radially by the concave dispersion surface and directly emitted vertically downward. It returns to the inclined surface portion of the light and is divided into light that is directed vertically downward by total reflection.
[0008]
An optical path suppression lens according to a second aspect of the present invention is the optical path suppression lens according to the first aspect, wherein a notch portion that is notched with a substantially constant thickness from the incident surface side to the inside of the second icicle-shaped portion is provided. There is something to prepare.
[0009]
Therefore, according to the optical path suppression lens of the invention of claim 2, in addition to the action of the optical path suppression lens of the invention of claim 1, the second icicle-shaped portion having the largest thickness as it is in the entire condensing part region. The thickness of the sheet is prevented from increasing by the notch.
[0010]
An optical path suppression lens according to a third aspect of the present invention is the optical path suppression lens according to the first aspect, wherein the optical path suppression lens has a convex curved surface having a constant curvature at one end in the width direction when viewed from one end surface direction in the depth direction. A connecting curved surface having a concave connecting curved surface formed of a concave curved surface that can be meshed with the convex connecting curved surface at substantially the same curvature as the convex connecting curved surface, and the convex connecting curved surface and the concave connecting curved surface. When the convex connection curved surface of one optical path suppression lens and the concave connection curved surface of the other optical path suppression lens are meshed with each other in the two optical path suppression lenses, the two optical path suppression lenses have a substantially line symmetrical positional relationship. This is a position to be kept, and is centered on a substantially line-symmetric axis of symmetry of the two optical path suppression lenses.
[0011]
Therefore, according to the optical path suppression lens of the invention of claim 3, in addition to the action of the optical path suppression lens of the invention of claim 1, even if the condensing portions of the two optical path suppression lenses change the angle at the coupling position, A symmetrical positional relationship is maintained.
[0012]
A light collecting device according to a fourth aspect of the present invention has a light receiving portion that receives and extracts sunlight energy, and radiated light passes through each of the optical path suppression lenses according to the first aspect when viewed in the north-south direction. It is arranged so that it becomes an angle to go.
[0013]
Here, the light receiving unit includes a heat storage tank that stores sunlight energy as heat energy, a solar battery or a steam engine that converts the energy into electric energy, an regenerator of an absorption refrigeration cycle, and the like.
[0014]
Therefore, according to the condensing device of the invention of claim 4, the incident light incident on any of the plurality of optical path suppression lenses of claim 1 is all after transmission without substantially depending on the incident angle that changes every moment. It is condensed toward the light receiving part.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described. FIG. 1 is an end view showing an optical path suppression lens according to an embodiment of the present invention as viewed from one end face in the depth direction. The optical path suppressing lens 1 according to the embodiment of the present invention is made of a transparent methacrylic resin (hereinafter simply referred to as MMA) having a refractive index of approximately 1.49, and as shown in FIG. When viewed from the end face, a plurality of light collecting portions 2 having the same shape are connected. Each condensing part 2 is continued substantially linearly in the depth direction, and the entire optical path suppression lens 1 has a substantially flat plate shape. As will be described below, the optical path suppression lens 1 according to the embodiment of the present invention can suppress the traveling direction of sunlight in which the incident angle changes every moment due to the influence of the rotation of the earth within a substantially constant range. In particular, since the effect is obtained in the entire sunshine hours from sunrise to sunset, it can be used stationary. And the whole is flat form, and space saving and manufacturing cost can be reduced.
[0016]
As shown in FIG. 2, each condensing unit 2 has a flat surface portion 3 positioned substantially at the center of the incident surface side when viewed from one end surface direction, and approximately 45 on the radiation surface side following the left and right ends of the flat surface portion 3. An inclined surface portion 4 inclined at an angle of 4 to 5 times that of the flat surface portion 3 and an inclined surface portion 4 of another condensing portion 2 adjacent to the other end of each inclined surface portion 4 forming a concave curved surface. And a connecting surface 5 connected to. FIG. 2 is an enlarged end view showing a condensing portion of the optical path suppression lens according to the embodiment of the present invention. Further, the condensing unit 2 is located on the radiation surface side substantially at the center of the radiation surface side of each condensing unit 2, has a concave curved surface, and jumps up the incident light incident at a critical angle by total reflection, A condensing surface 7 having a convex curved surface following the flip-up surface 6 and having a width of two-fifths to three-fifths of the inclined surface, and a concave curved surface following the condensing surface 7 and the inclined surface 4. A dispersion surface 8 having a width of 1/5 to 1/3 of the above, a first icicle portion 9 that converges and protrudes following the dispersion surface 8, and the other adjacent to the first icicle portion 9 The second icicle-shaped portion 10 is connected to the first icicle-shaped portion 9 of the condensing portion 2 and protrudes by converging. The second icicle-shaped portion 10 is larger than the first icicle-shaped portion 9, but the notch 5a is formed on the connecting surface 5 on the incident surface side so that the thickness of the entire second icicle-shaped portion 10 is substantially constant. Is formed. The notch portion 5a prevents the thickness of the second icicle-shaped portion 10 that is the largest in the entire region of the light collecting portion 2 from being increased, and minimizes deformation distortion during molding by the mold. It can reduce the optical path control effect as designed.
[0017]
A convex connecting curved surface 11 having a constant curvature and a convex curved surface is formed at one end in the width direction when viewed from the one end surface direction in the depth direction of the optical path suppressing lens 1 as shown in FIG. At the other end, as shown in FIG. 3 (b), a concave connecting curved surface 12 is formed which is a concave curved surface that can be meshed with the convex connecting curved surface 11 with substantially the same curvature as the convex connecting curved surface 11. Has been. 3A is an explanatory view showing the convex connection curved surface 11 of the optical path suppression lens according to the embodiment of the present invention, and FIG. 3B is an explanation showing the concave connection curved surface 12 of the optical path suppression lens according to the embodiment of the present invention. FIG. As shown in FIG. 4, the positional relationship between the convex connection curved surface 11 and the concave connection curved surface 12 is such that the convex connection curved surface 11 of one optical path suppression lens 1 and the other optical path suppression lens 1 in two optical path suppression lenses 1. When the concave connecting curved surface 12 is engaged with each other, the two optical path suppression lenses 1 maintain a substantially line-symmetrical positional relationship, and the center 14 is positioned on the substantially line-symmetrical symmetry axis 13 of the two optical path suppression lenses 1. ing. FIG. 4 is an explanatory view showing a connected state of a plurality of optical path suppression lenses according to the embodiment of the present invention. Therefore, as shown in FIG. 5, even if the angles of the two optical path suppression lenses 1 are changed at the connection position, the optical path suppression lenses 1 are maintained in a substantially line-symmetrical positional relationship, and a plurality of optical path suppression lenses 1 can be easily arranged with good appearance. . FIG. 5 is an explanatory view showing a connection state of a plurality of optical path suppression lenses according to the embodiment of the present invention following FIG.
[0018]
Next, characteristics of the optical path suppression lens 1 according to the embodiment of the present invention will be described with reference to FIGS. In the following description, it is assumed that the linearly continuous direction of the light collecting unit 2 is used toward the north and south. FIG. 6 is an explanatory diagram showing a state in which light is incident on the optical path suppression lens according to the embodiment of the present invention at an incident angle of 15 ° when viewed from the end surface direction in the depth direction. FIG. 7 is an explanatory diagram showing a state in which light is incident on the optical path suppression lens according to the embodiment of the present invention at an incident angle of 30 ° when viewed from the end surface direction in the depth direction. FIG. 8 is an explanatory diagram showing a state in which light is incident on the optical path suppression lens according to the embodiment of the present invention at an incident angle of 45 ° when viewed from the end surface direction in the depth direction. FIG. 9 is an explanatory diagram illustrating a state in which light is incident on the optical path suppression lens according to the embodiment of the present invention at an incident angle of 60 ° when viewed from the end surface direction in the depth direction. FIG. 10 is an explanatory diagram showing a state in which light is incident on the optical path suppression lens according to the embodiment of the present invention at an incident angle of 75 ° when viewed from the end surface direction in the depth direction. As shown in FIGS. 6 to 10, according to the optical path suppression lens 1 of the present embodiment, the traveling direction of transmitted light is substantially vertically downward and maintained in a substantially constant direction even when the incident angle is changed variously. This characteristic is not shown in all incident angles, but is exhibited in the entire range from 0 ° to 90 °.
[0019]
Now, the principle of keeping the traveling direction of transmitted light substantially constant regardless of the incident angle will be described in detail. The inclined surface portion 4 emits light incident from one of the two inclined surface portions 4 of the condensing portion 2 from the opposite emission surface when the incident angle is relatively large as 60 ° or more as shown in FIGS. 9 and 10. When the light travels backward from the other radiation surface to the incident surface later, the light travels back to the radiation surface side again by total reflection. As a result, the traveling direction of the transmitted light is maintained in a direction perpendicular to the drawing. In addition, when the incident angle is relatively large as described above, most of the incident light is incident from one of the two inclined surface portions 4 of one light collecting portion 2 and totally reflected by the other inclined surface portion 4. However, the condensing surface 7 has a convex shape so that the light incident from the one inclined surface portion 4 is converged to easily reach the other inclined surface portion 4.
[0020]
Note that light incident from a relatively upper part of the incident surface (particularly the flat portion 3) tries to pass through without changing the traveling direction vertically downward if nothing is done, so there is a problem when the incident angle is relatively large. However, as shown in FIGS. 9 and 10, the incident light is guided to the inclined surface portion 4 by being totally reflected by the flip-up surface 6 and is finally corrected substantially vertically downward.
[0021]
As shown in FIGS. 7 to 9, incident light incident below the inclined surface portion 4 or from the connection surface 5 is incident between the opposing surfaces by the first ice column portion 9 or the second ice column portion 10. Accordingly, the light is totally reflected a plurality of times to limit the traveling direction of the transmitted light substantially vertically downward. As shown in FIG. 9, the dispersive surface 8 has a radial shape because the transmitted light that could not reach the light collecting surface 7, the first icicle-shaped portion 9, and the second icicle-shaped portion 10 has a concave shape. Is diffused into light that is directly radiated vertically downward and light that is returned to the other inclined surface portion 4 to be vertically downward by total reflection. Based on the principle as described above, the optical path suppression lens 1 of the present embodiment can radiate while maintaining the traveling direction of incident light incident at various incident angles in a substantially constant direction.
[0022]
In addition, one condensing part 2 of the optical path suppression lens 1 is bilaterally symmetric when viewed from one end surface direction, and similarly in the entire range where the incident angle reaches 90 ° in the opposite direction to the case described above. The traveling direction of the transmitted light is suppressed to a substantially constant direction. Therefore, the traveling direction of the transmitted light can be maintained in a substantially constant direction over the entire range from 0 ° to ± 90 °.
[0023]
As shown in FIG. 11, the optical path suppression lens 1 according to the embodiment of the present invention having the above-described characteristics is provided with a predetermined amount of sunlight that changes with time due to the rotation of the earth only by arranging a plurality of dome shapes. It is possible to focus on the range. FIG. 11 is an explanatory diagram showing an example of a condensing device using the optical path suppression lens according to the embodiment of the present invention. A condensing device 21 shown in FIG. 11 connects a plurality of optical path suppression lenses 1 with the convex connection curved surface 11 and the concave connection curved surface 12 described with reference to FIGS. It is arranged so that the emitted light from each optical path suppression lens 1 is concentrated at one point, and a light receiving unit 22 that receives and extracts sunlight energy is arranged at a position where the emitted light is concentrated. Yes. Here, the light receiving unit 22 includes a heat storage tank that stores sunlight energy as heat energy, a solar cell or a steam engine that converts the energy into electric energy, a regenerator of an absorption refrigeration cycle, and the like.
[0024]
The incident light from above, as indicated by a two-dot chain line in FIG. 11, changes in incident angle every moment before incident, but substantially depends on the incident angle incident on the optical path suppression lens 1. Without being focused toward the light receiving unit 22.
[0025]
Thus, according to the condensing device 21 using the optical path suppression lens 1 according to the embodiment of the present invention, sunlight energy is condensed in the light receiving unit 22 to obtain solar energy having a concentration higher than that of direct sunlight. be able to. In particular, the sunlight can be condensed even when the sunlight is less diluted or scattered than usual, such as in winter or on a cloudy day. In addition, the optical path suppression lens 1 according to the embodiment of the present invention can maintain the traveling direction of transmitted light in a substantially constant direction over the entire range of incident angles from 0 ° to ± 90 °. There is no need to perform complicated processing such as tracking the lens 1 according to the incident angle of incident light throughout the day. Therefore, solar energy can be condensed and used effectively at a very low cost. For example, when the light receiving unit 22 is a heat storage tank, various uses such as obtaining hot water, a heat source for heating, a heat source for an absorption refrigeration cycle, and solar thermal power generation are conceivable. Moreover, when the light-receiving part 22 is a solar cell panel, solar power generation can be performed directly. In particular, when operating an absorption refrigeration cycle or performing solar power generation, not only can energy be used effectively, but peak cuts in power demand can be promoted, and power generation facilities of electric power companies can be reduced.
[0026]
By the way, the optical path suppression lens 1 according to the embodiment of the present invention is made of a transparent methacrylic resin (MMA) having a refractive index of 1.49. It is designed in a shape that can be kept within a certain angle range, but if it is designed in a shape that can keep the traveling direction of transmitted light in a substantially constant angle range optimally according to the refractive index, it is made of another material with a different refractive index. It doesn't matter.
[0027]
【The invention's effect】
Since the present invention is configured as described above, the following effects can be obtained.
[0028]
According to the optical path suppressing lens of the first aspect of the present invention, when the incident angle of the incident light is relatively large as 60 ° or more, the incident light is incident from one of the two inclined surface portions of the one light collecting portion. Most of the light is totally reflected by the other inclined surface portion, the traveling direction of transmitted light is limited to a substantially constant direction, and the convex condensing surface converges the light incident from the inclined surface portion to the other inclined surface portion. In addition, the incident light incident at a relatively large incident angle of 60 ° or more from the plane portion that is relatively above the incident surface and the vicinity thereof is totally reflected by the jumping surface and guided to the inclined surface portion. Finally, it is corrected to be substantially vertically downward, and incident light incident below the inclined surface or from the connecting surface is incident on the incident angle between the opposing surfaces by the first ice column or the second ice column. Depending on the total reflection, the transmitted light travels almost vertically. In addition, the transmitted light that was limited to the downward direction and could not reach the condensing surface, the first icicle-shaped portion, or the second icicle-shaped portion was diffused radially by the concave dispersion surface and directly directed vertically downward It is divided into light radiated to the sun and light that returns vertically to the other inclined surface part and is vertically lowered by total reflection, so the direction of incident light whose incident angle changes from moment to moment can be seen throughout the day from sunrise to sunset. It can be suppressed in a substantially constant direction extremely efficiently.
[0029]
According to the optical path suppression lens of the second aspect of the invention, in addition to the effect of the optical path suppression lens of the first aspect of the invention, the thickness of the second icicle-shaped portion where the thickness is the largest among the entire condensing portion as it is. Since the thickness is prevented from being increased by the notch, deformation distortion at the time of molding by the mold is reduced to the minimum, and the optical path suppressing effect as designed can be exhibited.
[0030]
According to the optical path suppression lens of the third aspect of the invention, in addition to the effect of the optical path suppression lens of the first aspect of the invention, the two optical path suppression lenses are maintained in a substantially line-symmetrical positional relationship even if the angle is changed at the connecting position. Therefore, a plurality of optical path suppression lenses can be easily arranged with good appearance.
[0031]
According to the condensing device of the fourth aspect of the present invention, the incident light incident on any one of the plurality of optical path suppression lenses of the first aspect of the present invention is all received after being transmitted without substantially depending on the incident angle that changes with time. Since the light is condensed toward the solar light, the solar energy is condensed in the light receiving portion, and the solar energy having a higher concentration than the direct sunlight can be obtained. In particular, the sunlight can be condensed even when the sunlight is less diluted or scattered than usual, such as in winter or on a cloudy day. Moreover, since the traveling direction of the transmitted light can be maintained in a substantially constant direction over the entire range from 0 ° to ± 90 °, the installed optical path suppression lens can be tracked according to the incident angle of the incident light, etc. There is no need to do any complicated processing throughout the day. Therefore, solar energy can be condensed and used effectively at a very low cost. For example, when the light-receiving unit is a heat storage tank, various uses such as obtaining hot water, a heat source for heating, a heat source for an absorption refrigeration cycle, and solar thermal power generation are conceivable. Moreover, when a light-receiving part is a solar cell panel, solar power generation can be performed directly. In particular, when operating an absorption refrigeration cycle or performing solar power generation, not only can energy be used effectively, but peak cuts in power demand can be promoted, and power generation facilities of electric power companies can be reduced.
[Brief description of the drawings]
FIG. 1 is an end view showing a state where an optical path suppressing lens according to an embodiment of the present invention is viewed from one end face in a depth direction.
FIG. 2 is an enlarged end view showing a condensing portion of the optical path suppression lens according to the embodiment of the present invention.
3A is an explanatory view showing a convex connection curved surface of an optical path suppression lens according to an embodiment of the present invention, and FIG. 3B is an explanatory view showing a concave connection curved surface of an optical path suppression lens according to an embodiment of the present invention. It is.
FIG. 4 is an explanatory diagram showing a connection state of a plurality of optical path suppression lenses according to an embodiment of the present invention.
FIG. 5 is an explanatory diagram showing a connection state of a plurality of optical path suppression lenses according to the embodiment of the present invention following FIG. 4;
FIG. 6 is an explanatory diagram illustrating a state in which light is incident on the optical path suppression lens according to the embodiment of the present invention at an incident angle of 15 ° when viewed from one end surface direction in the depth direction.
FIG. 7 is an explanatory diagram illustrating a state in which light is incident on the optical path suppression lens according to the embodiment of the present invention at an incident angle of 30 ° when viewed from the end surface direction in the depth direction.
FIG. 8 is an explanatory diagram illustrating a state in which light is incident on an optical path suppression lens according to an embodiment of the present invention at an incident angle of 45 ° when viewed from one end surface direction in the depth direction.
FIG. 9 is an explanatory diagram illustrating a state in which light is incident on the optical path suppression lens according to the embodiment of the present invention at an incident angle of 60 ° when viewed from one end surface direction in the depth direction.
FIG. 10 is an explanatory diagram illustrating a state in which light is incident on the optical path suppression lens according to the embodiment of the present invention at an incident angle of 75 ° when viewed from the end surface direction in the depth direction.
FIG. 11 is an explanatory diagram showing an example of a condensing device using the optical path suppression lens of the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Optical path suppression lens 2 Condensing part 3 Flat part 4 Inclined surface part 5 Connection surface 5a Notch part 6 Flip-up surface 7 Condensing surface 8 Dispersion surface 9 1st ice column part 10 2nd ice column part 11 Convex connection curved surface 12 Concave shape Connecting curved surface 13 Symmetry axis 14 Center 21 Condensing device 22 Light receiving part
